Cement compositions



Patented July 11, 1950 UNI-TED STATE CEMENT COMPOSITIONS HerbertGoldstein, Elizabeth, N. J assignorto L.

Sonneborn Sons, Inc.,

ware

a corporation of Dela- No Drawing. Application April 29, 1949, SerialNo. 90,540

This invention relates to new and useful improvements in cementcompositions and is a continuation in part of my application Serial No.v622,935, filed October 1'7, 1945, now abandoned.

Cement or concrete laying or surfacing requires a base of suitableroughness and undercuts in order to securely lock or anchor the cementor concrete thereto applied. When laying cement or concrete on a surfacethat is relatively smooth, as for instance, a stone, stone composition,cement or concrete, or other masonry surface, it is necessary toprecondition that surface by suitably roughening the same. Thisroughening may be carried out by mechanical means such as chiseling orchipping the surface in a manner to provide the requisite roughness witha maximum of undercuts. This procedure is unsatisfactory, does not givein all cases the desired degree of bond and is uneconomical and timeconsuming. The results are particularly unsatisfactory when the cementor concrete laid on the base surface possesses different characteristicsof heat expansion and cold contraction from that of the base material.

The difficulties involved in obtaining a satisfactory bond between abase surface and the cement or concrete to be laid thereon areparticularly pronounced in patch or repair work or resurfacing of apreviously existing cement or concrete surface. In those cases, thepreconditioning of the old cement or concrete base in the requisitemanner for satisfactory bonding of the newly to be laid cement orconcrete is difficult, and in the majority of cases will not givesatisfactory results. This is especially true where the job is subjectand exposed to the exigencies of climatic and weather influences.Attempts have been made to overcome some of the difficulties of thesurface preparation involving the mechanical roughening and undercuttingof the base surface by the use of a primer which itself possesses somebonding characteristics with respect to the base surface and afterapplication would set on the base with an exposed surface exhibiting 'acertain amount of roughness. However, such primer applications are inthe majority of cases not too successful as either the bond'betweenprimer and bases or the bond between superimposed cement or concrete andprimer or both of these prove of insufficient anchorage for the laidcement or concrete to the base onto which it is applied.

Attempts have also been made, to compound asphalt into cementcompositions for the purp s thereb i in suita le Patching 4 Claims. (Cl.260-29-6) compound. However, such compositions are also not self-bondingand require a suitable asphalt primer. These compositions arefurthermore objectionable due to the dark color imparted to the mixtureby the asphalt.

One object of the invention is a cement composition which is inherentlysubstantially selfbonding to any substantially self-sustaining basesurface to which it is applied without the necessity of preconditioningthe base surface or the use of a primer thereon.

A further object of the invention is such a cement compositioninherently so self-bonding to an extent that temperature changesdifferentially affecting the material of the base and the concretecomposition in accordance with the invention laid onto the same will notsever the bond. 1

A still further object of the invention is such a cement compositionspecifically adapted for patching or resurfacing of worn concretesurfaces without the necessity of pre-roughening the existing concretesurface or applying a primer thereto.

These' and still further objects of the invention will appear from thefollowing description.

The Portland cement composition in accordance with theinventionessentially comprises a Portland cement composition and.intimately dispersed therethrough an aqueous colloidal dispersion ofcumaron resin, said aqueous dispersion not containing substantially inexcess of by weight of the cumaron resin.

For best results, the amount of cumaron resin in the cement compositionin accordance with my invention should be such that there is presentabout one part by dry weight of cumaron resin for about every 15-50 andpreferably about every 40-50 parts by dry weight of Portland cement. I Y

Aqueous colloidal dispersions of cumaron resin frequently referred to ascumaron emulsions may be prepared in accordance with well knownprocedures and are commercially available with cumaron resins of varyingmelting points. The melting point of the cumaron resin when used inaccordance with the invention determines to) some extent the finalcharacteristics of the Portland cement composition after it has beenlaid and set. The lower the relative melting point of the cumaron resinthe relatively softer and more resilient will be the ultimate cementcomposition after setting. Such relatively low melting point cumaronresin cement composition,

.hQWtY t qes ql qssess he-samecomp e ive water.

strength as such cement composition using a cumaron resin of arelatively higher melting point. Such latter cement composition will be,on the other hand, harder than the product containing the cumaron resinof lower melting point. It is thus possible to vary the characteristicsof the finally desired cement composition in accordance with specificdemands or requirements. .I have found, however, that a cumaron resinhaving a melting point lower than substantially 35 C. will not produce asatisfactory Portland cement composition as the resulting productexhibits too high a degree .,of softness. 9n the other hand, I havediscovered that-.a .cumaron resin having a melting point in excess ofsubstantially 55 C. will not yield a satisfactory Portland cementcomposition because the resultin 7 I other; aggregatedue to ;the,;dange,r ,of coalescence of the cumaron particles. fl'hecumaron resin .may bezinccrmcratedeby adding-the-same to the cement -or-,to theeauein .wateror tothe. aggreat.e,;.or toflaymixture of any or. all :of thesesubstances makin up the .cementnomp s t n.

The terms "cementf cement composition or such similar expressions, asherein "used are intended to designate any Portland cement :composi ionwhether nea ,.:i- .e-,:Wi hc.1.1t :the addition of sand and/or a regate,.crinjhe form of a concreteeorfiimilar composition, 13., one ,containinsa and/ r a re ate- If desired, it is possible ,to isatisfactorilyrincorporate in the cement composition.prematerial in accorda w th theinv nt o asbestos -cr. ot

accountin the determinationof the gauge water for the preparation 50fthe final cement: or. concrete mix. In -;a limiting case thereforethegmimmum water :oontent ofpthe -cumaron {res-in emul- 'sionor"-dispersion ;is defined by the total-amount of gauging water requiredfor the particular-cement-or concrete composition, in which-event allof-such -g'auging water would thus ;be introduced .bY- WQiQ'l'lbfOf the=water-content of :the-aqueous cumaronemulsion or dispersion.

The -fol1o,wing--exampl-esare furnished by Way 65 ofiliustration and,not of limitation:

Example I Neat Portland cement was gauged with water *to plasticconsistency in the proportionof about 10 pounds of-Portland cement tofive pounds of The mixture was applied to a previously mechanicallyroughened concrete surface to a thickness of After the mix had hardened,

no uniform overall anchorage "was discernible and the absence of a realbond was manifest when a ten pound weight was dropped on the surface,whereupon the topping fractured.

Example II A mixture of Portland cement-sand and stone, in (theproportion of one bag of ,cement (about 94"1bs'.), two bags of s and(about 275 ;lbs.) and about 300 lbs. of stone and water to give awatercement ratio of 0.55 by weight (about 52 lbs.) was applied to aconcrete base, which had been -mecha-nical1y roughened, to a thicknessof 1 Examination of this. application after one week showed thatadhesion was by mechanical anchorage alonevand that the topping was heldin place by its .own weight. Impact of a ten "pound weight dropped froma height of six feet fractured the topping and upon removal of thefractured fragment, no positive bond between the topping and thesub-surface was discerned.

' Eramplc III Portland ,cement (about .94 lbs.) was gauged with water(about :52 lbs.) to plastic, ,cons istency, the water vcarrying. indispersion 1 parts of cumaron emulsion ,by volume (about 6 lbs. dry w htcumar n r n Th plas icmixtu was ppli t a plan cc cr tesurfac o t ing anyprevious preparation, to .aithicknessyof f. Inspection ,of this,applicaticn after seven days showed him adhesion throughout andfflheimpact of v a ten pound weight rdrqpped from a height of six feet,vginndented 'butfailed to-fr t rethe tonpine- Tests fc scnn n ssi ndcated a permane nd throu h ut- -Eccmplely A.. crtland. me onc ete .nn'was made p inaccordance with *E'xampleTIwith the except ont /2 a c i u nr ne ul cnb v um (about 2"lbs. by weight of resin) was dispersed in thegaugingwater. The .mix was applied on a straight concrete 'base withoutany previous .preparation'thereof, to a'thickness of1 /g 'Upon testingsubstantially as injthe previous examples, a uniform permanent "bond wasevidenced throughout.

Inthe following examples, applications of' the cement composition inaccordance with the 'inventiom such as for theglaying of entire surfacesor for-the-patch work of ,Wornsurfaces, .are describedbywayofillustration -Aninterio c et oor.inala cratcry.buil ins .w chbadbee -bedlywc n by t efific was .r rsurfac di acco dan w th 9wine prcedure: .An ix comprising onebag Portla d cement -.v(ab,out, Qilbs.) tworbags sand, (about 2'75 1bs.) about A ,lbs. of 50% .cumarcnemulsion (a ob .ner dry wei htcuma c re n wa gauged v,with lsufiicient water .to givea plastic workable mi and the lmi ewas .spreadeev r h flo r. and sceededltotalevelsu ta Th .th c n s wcf the topping. ranged .from ,to /4"depend necn tbeedenth .cf the wor e ssh l andiruts n ,th ificcr- ."ledgescf .theharea were eath red dcunito thelle el flth adi-a ents u dcrin Th toppin w sallcwe tcset fo tw h u a d the ts ec .t cweled tc asmooth. su

f e. nt d nnhc .late .the surface wa inspectedandfit was seen that auniform o'sitive bond existed throughoutbetweenthe topping and h es I sction a ;thelr uri c d.area had be n 'inus six wee ss, during hi'reriod"it"hadbeen-subi-ected to "rolling ambulatory traflic, revealedonly a number of random hairline cracks at the feathered edge perimeterof the re-surfaced area, but no fractures or evidence of loss of bondthroughout.

Example VI An outdoor concrete stairway sustained severe damage by wayof spalling and cracking due to frost. Treads were spalled to a depth ofA of an inch and the risers exhibited numerous cracks. The vertical sidewalls were spalled to a depth of 5 A mixture of one bag cement (about 94lbs.), about 4 lbs. of 50% cumaron emulsion and two bags sand (about 275lbs.) was gauged with suflicient water to give a plastic mix (about 50lbs. water). The mix was then troweled over all the spalled and brokenrisers so that the new and old surface formed a continuous level. Withintwenty-four hours, all patched areas were hard and the treads in shapeto receive traffic. Inspection six Weeks later revealed no sign ofdisruption of bond.

The foregoing description is for purposes of illustration and not oflimitation and it is therefore my intention that the invention belimited only by the appended claims or their equivalents wherein I haveendeavored to claim broadly all inherent novelty.

I claim:

1. A substantially self-bonding cement compo sition comprising aPortland cement-composition and intimately dispersed therethrough anaqueous colloidal dispersion of not in excess of substantially 50% byweight of cumaron resin, said cumaron resin being present tosubstantially yield about one part by dry weight of cumaron resin forabout every 15-50 parts by dry weight of Portland cement present in saidcomposition, the water in said dispersion not substantially exceedingthe total gauging water required for said composition.

2. A substantially self-bonding cement composition in accordance withclaim 1 in which said cumaron resin is present to substantially yieldabout one part by dry weight of cumaron resin for about every -50 partsby dry weight of Portland cement present in said composition.

3. A substantially self-bonding cement composition in accordance withclaim 2 in which said cumaron resin has a melting point substantiallybetween 35 and 55 C.

4. Method of preparing a substantially selfbonding cement compositionwhich comprises intimately dispersing through 2. Portland cementcomposition an aqueous colloidal dispersion of not in excess ofsubstantially by weight of cumaron resin having a melting pointsubstantially between 35 and C. and present substantially to yield aboutone part by dry weight of cumaron resin for about every 15-50 parts bydry weight of Portland cement, the water in said dispersion notsubstantially exceeding the total gauging water required for saidcomposition.

HERBERT GOLDSTEIN.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 1,299,798 Skinner Apr. 8, 19191,991,007 Bonney et al Feb. 12, 1935

1. A SUBSTANTIALLY SELF-BONDING CEMENT COMPOSITION COMPRISING A PORTLANDCEMENT COMPOSITION AND INTIMATELY DISPERSED THERETHROUGH AN AQUEOUSCOLLOIDAL DISPERSION OF NOT IN EXCESS OF SUBSTANTIALLY 50% BY WEIGHT OFCUMARON RESIN, SAID CUMARON RESIN BEING PRESENT TO SUBSTANTIALLY YIELDABOUT ONE PART BY DRY WEIGHT OF CUMARON RESIN FOR ABOUT EVERY 15-50PARTS BY DRY WEIGHT OF PORTLAND CEMENT PRESENT IN SAID COMPOSITION, THEWATER IN SAID DISPERSION NOT SUBSTANTIALLY EXCEEDING THE TOTAL GAUGINGWATER REQUIRED FOR SAID COMPOSITION.